org.jetbrains.kotlin.resolve.calls.checkers.NamedFunAsExpressionChecker.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
package org.jetbrains.kotlin.resolve.calls.checkers
import com.intellij.psi.PsiElement
import org.jetbrains.kotlin.config.LanguageFeature
import org.jetbrains.kotlin.diagnostics.Errors.ANONYMOUS_FUNCTION_WITH_NAME
import org.jetbrains.kotlin.diagnostics.reportDiagnosticOnce
import org.jetbrains.kotlin.psi.KtNamedFunction
import org.jetbrains.kotlin.psi.KtPsiUtil
import org.jetbrains.kotlin.psi.psiUtil.isFunctionalExpression
import org.jetbrains.kotlin.resolve.calls.model.ExpressionValueArgument
import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
import org.jetbrains.kotlin.utils.addToStdlib.safeAs
/**
* That checker used to check that only anonymous functions are used as function arguments
*
* Examples:
*
* fun foo(obj: Any) {}
* foo(fun named() {}) // bad
*
* // here `if` is synthetic function call
* val x = if (b) fun named1() {} else fun named2() {}
*/
object NamedFunAsExpressionChecker : CallChecker {
override fun check(resolvedCall: ResolvedCall<*>, reportOn: PsiElement, context: CallCheckerContext) {
if (!context.languageVersionSettings.supportsFeature(LanguageFeature.NewInference)) return
for (argument in resolvedCall.valueArguments.values.filterIsInstance(ExpressionValueArgument::class.java)) {
val expression = KtPsiUtil.deparenthesize(argument.valueArgument?.getArgumentExpression()) as? KtNamedFunction ?: continue
if (!expression.isFunctionalExpression()) {
/*
* There is one another place, where ANONYMOUS_FUNCTION_WITH_NAME is reported
* ([org.jetbrains.kotlin.types.expressions.FunctionsTypingVisitor]), so in some cases there is
* can be duplicated diagnostic. It is a little problem that should go when we will resolve assignments
* as calls, so that checker will report all cases of ANONYMOUS_FUNCTION_WITH_NAME diagnostic.
*/
context.trace.reportDiagnosticOnce(ANONYMOUS_FUNCTION_WITH_NAME.on(expression.nameIdentifier!!))
}
}
}
}